Switch index mechanism



April 4-, 1939. NEWMAN 2,153,430

SWITCH INDEX MECHANISM Filed Nov. 20, 1937 Z a i 4 4 5 Z a lhlVENTORInward Newman ATTORNEY Patented Apr. 4, 1939 UNITED STATES.

PATENT OFFICE SWITCH INDEX MECHANISM Application November 20, 1937,Serial No.'1'75,812 1 Claim. (01. 74-97) This invention relates toelectric switches and more particularly to indexing means therefor.

An object of the invention is to improve the indexing means for electricswitches.

'. Other objects of the invention will be apparent from the followingdescription and accompanying drawing taken in connection with theappended claim.

The invention comprises the features of con? in struction, combinationof elements, arrangement of parts, and methods of manufacture andoperation referred to above or which will be brought out and exemplifiedin the disclosure hereinafter set forth, including the illustrations inthe drawing.

In the drawing: Figure 1 is a perspective view of a portion of anelectric switch showing the index means therefor; Figure 2 is a top viewof the index mechanism;

Figure 3 is a section on the line 3-3 of Figure 2;

Figure 4 shows a modified means for mounting part of the indexstructure; and

Figure 5 is a section on the line 5--5 of Figure 4.

According to the invention a switch index means is provided which issuitable for rotarytype multi-position switches. The index mechanism isparticularly well adapted for use in switches of the type shown anddescribed in H. Hall application Serial No. 93,809, filed August 1,1936. The mechanism is also adapted for use with other types ofswitches.

While a preferred embodiment of the invention is described herein, it iscontemplated that considerable variation may be made in the method ofprocedure and the construction of parts without departing from thespirit of the invention.

In the following description and in the claim,

parts will be identified by specific names for convenience, but they areintended to be as generic in their application to similar parts as theart will permit.

Referring to the drawing and particularly to Figures 1, 2 and 3 andplate It comprises part of a switch structure through which the switchcontrol shaft ll passes. Plate I0 is provided with a pair of oppositelydisposed upturned flanges i2 from which one or more sets of switchrotorstator assemblies can be supported for control by the shaft II, therotors being keyed to the shaft. Flanges l2 may be provided, as shown,with small cars l3 for use in mounting or to serve as soldering lugs forattaching a ground connection to the switch. Plate ll is also providedwith a pair of upturned lugs ll which are notched on their inner edgesto receive the ends of a leaf spring. Shaft II is supported for rotationin a bushing 15 which is secured in a central aperture in plate III. Alock washer ll fits into a groove in shaft I l at the end of bushing l5to prevent longitudinal movement of the shaft in an inward direction.

The inner end of shaft II is milled to provide 10 a flat tongue ill, theend ll of which is made somewhat narrower than the rest.

An indexing disc i9, preferably of metal, is provided with a centralaperture having a circular portion and a pair of side notches which are15 adapted to fit over the tongue I! of the shaft so that disc l9 restsagainst the end of the round portion of the shaft. The shoulders ontongue portion ll may be upset over disc It to secure it to the shaft. Awasher 20 is disposed between 20 disc l9 and the end of bushing I5 andserves to space disc ill from plate Ill. The edge of disc i9 is formedwith an annular series of rounded teeth 2| so as to provide spacednotches 22 between them, corresponding to the desired switch 26positions.

Indexing spring 23, comprising a narrow leaf spring has a rounded hump24 at its middle and is bent into resilient U-shaped loops 35 near itsends. The extreme ends are bent back to pro- 30 vide hooked portions 25.The spring is mounted on plate ID by compressing it between lugs M withportions 25 hooked into the notches in lugs l4. Central hump 24 isthereby arranged to press into the notches 22 of disc 19 under pressureof 36 the spring.

It will be seen that this provides an indexing means for determining thestopping positions of the switch. When shaft I i is turned by a knob orother means mounted on its outer end, whereby 40 the switch contacts aremoved into or out of engagement, the spring 23 will ride over therounded teeth 2| and the hump 24 in the spring will always tend to bringthe switch to rest in a position such that the hump 24 presses into one45 of the notches 22. This may correspond to a closed or an openposition of the switch contacts, as desired.

Plate [0 is also provided with a struck-up ear 26 and disc I! with apair of downwardly project- 50 ing ears 2! which come into engagementwith car 26 at certain switch positions to limit the rotation of theswitch.

several switch sections are to be controlled by the same shaft and indexmeans. According to this arrangement a round shaft 18 is provided with areduced recessed circular section 2! at its end. Disc I. fits over thereduced circular section 20 so as to rest against the end of the largercircular part of shaft 2. and a pair of tongues II are stripped downfrom the wall of reduced portion 20 to flt into the two notches in discI. A flat shaft Ii having a tapered end 32 may then be wedged into therecess and slots in the end of the round shaft. Shaft 3| passes throughthe various switch sections and is keyed to the rotor members of eachsection so as to control the rotation thereof.

It is evident that a switch index mechanism is provided according to thepresent invention which is simple andeconomical of construction andfool-proof in operation. Should the index spring 2! become damaged orbent it can readily be replaced without disassembling the entire switch.

While the present invention, as to its objects and advantages; has beendescribed herein as carried out in specific embodiments thereof, it isnot desired to be limited thereby but it is intended to cover theinvention broadly within the spirit and scope of the appendedclaim.

What is claimed is:

An electric switch index mechanism comprising a switch mounting plate, arotor control shaft passing therethrough, a notched disc mounted on saidshaft to rotate therewith, said disc being adjacent said mounting plate,a pair of opposed projections upstanding from said mounting plate beyondthe edge of said notched disc, and a replaceable index spring mountedbetween said projections, said index spring comprising a leaf springhaving a central disconformity engaging the edge of said notched disc,the ends of said leaf spring being angularly disposed with respect tothe body of said spring and having hooked ends engaging and hookingagainst the inner sides of said upstanding projections whereby saidspring is held in compression between said projections. V

